SOLUTION: How do you.. Find the value of "K" with the the roots being 3x^2+kx+2=1 be real?

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Question 390065: How do you.. Find the value of "K" with the the roots being 3x^2+kx+2=1 be real?
Answer by richard1234(7193) About Me  (Show Source):
You can put this solution on YOUR website!
The discriminant of the function (i.e. b%5E2+-+4ac) must be nonnegative. Substituting a = 3, b = k, c = 2 in:

k%5E2+-+4%283%29%282%29+%3E=+0

k%5E2+%3E=+24

k+%3E=+2sqrt%286%29 or k+%3C=+2sqrt%286%29 (k can take on any of these values)